1. Field of the Invention
The present invention relates to a non-intrusive data transmission network for use in an enterprise facility. More particularly, the present invention relates to a system and method for implementing data transmission capabilities over a cable distribution system.
2. Description of Related Art
Data transmission networks are extremely well known and used throughout the prior art. Network characteristics which differentiate one network from another include: topology or the geometric arrangement of connection devices to the transmission medium; the data transmission technology used for data transfer (transmission protocols are the specification standards for sending types of data); and the substance used for the propagation of signals, i.e., the transmission media. The most common topology or general configurations of networks include the bus, star, and Token Ring topologies. Information networks can also be characterized in terms of spatial distance as local area networks (LAN), metropolitan area networks (MAN), and wide area networks (WAN). For simplicity, the discussion herein will categorize exemplary networks by the substance used for the propagation of signals, i.e., the transmission medium, because, as a practical matter, the threshold inquiry for an enterprise network frequently centers around the transmission media. Such medium substances include copper, e.g., twisted-wire pair, coaxial cable and power, fiber-optic cable, air, dielectric-slab waveguide, and even water. For the purposes herein, only copper, fiber-optic cable and air transmission mediums need be discussed.                Very often the type of transmission medium selected for the network determines the data transmission protocol employed thereon. For example, a local area networks (LAN) is a succession of points, nodes or access port interconnected by a communication line comprised of a specific transmission medium. Most LANs support the bi-directional (two-way) transmission of various data types, e.g., data, still and motion images and voice (sound). A PC LAN that makes use of a twisted pair transmission medium such as CAT 3, CAT 4, CAT 5, CAT 5E or CAT 6 is typically limited to one of the following transmission protocol: Asynchronous Transfer Mode (ATM), the IBM Token-Ring specification (IEEE 802.5), Ethernet standards (IEEE 802.3) including 10Base-T (also called Twisted Pair Ethernet), 100Base-T (or Fast Ethernet), and 1000Base-T (Gigabit Ethernet). The competing standard for Apple Macintosh networks is typically the AppleTalk network system (Apple Macintosh and AppleTalk are trademarked by and available from Apple Computer Inc., Cupertino, Calif.). The network types, transmission medium types and transmission protocols discussed herein are merely exemplary and not intended as an exhaustive list of all possible types. Moreover, those ordinarily skilled artisans in the relevant art will recognize that other exemplary types are presently known or will become known in the future. These examples types are proffered only for clarity and not intended to limit the scope of the present invention.        
Similarly, a LAN which makes use of coaxial cable may utilize one of the above identified transmission protocols. A LAN using AC power lines as its transmission medium may utilize the CEBus transmission standard (Consumer Electronics Bus, which is a trademark of and available from Electronic Industries Association Corporation, Washington D.C.). LANs operating over air transmission mediums employ any of a group of competing protocols under the IEEE 802.11 standard.
Data distribution systems are likewise extremely well known and used throughout the prior art. Data distribution systems differ from data networks in that data distribution systems were initially uni-directional, but recently that distinction is somewhat less accurate because of the trend toward the bi-directional transmission of data. Data distribution systems were initially intended for the uni-directional broadcasting of television and radio media from a common source or, alternatively, transmitting captured surveillance images to a common source. Data distribution systems are also distinguishable from networks in that they are generally configured as star topologies, or bus, but cannot be configured in a true ring topology. Data distribution systems also require transmission media having large bandwidths which typically restrict the transmission medium to coaxial cable and fiber. Exemplary distribution systems includes community antenna television or community access television (CATV), master antenna television (MATV), small master antenna television (SMATV) and closed circuit television (CCTV).
With the exception of CCTV, each of the above identified types of distribution systems are dependent on a broadband transmission medium, while LANs may be successfully operated over a less expensive twisted pair media. As a practical matter, while LAN components were once widely available with BNC connectors (British Nautical Connectors), presently virtually all LAN network components are ported with RJ-45 eight conductor twisted pair connections. CCTV distribution systems, which are largely relegated to surveillance systems, are a mix of coaxial, and 4, 6 and 8 conductor twisted pair media.
Therefore, in the event that an enterprise resolves to wire a transmission network over an existing facility, typically the most expeditious and cost effective means is by routing a twisted pair CAT medium throughout the existing structure. Conversely, if an enterprise decides to install a surveillance network in an existing facility, the most expeditious and cost effective means is by routing a dedicated coaxial cable for the distribution system. This often results in three separate and independent wiring networks, comprised of three different transmission media, each employing a disparate transmission technology over virtually the same area of the facility. Still more paradoxically, each of the networks may be ported in essentially the same location the facility for connecting to a specific device.
When taken separately, the cost of implementing any of these wiring networks in an existing facility must be strictly scrutinized not only due to their inherent cost of ownership, but also due to the expense of lost productivity during installation and the long term expenses associated with maintaining two or three separate networks which, essentially, may overlay one another in the facility.